Created: August 07, 2021
Modified: August 08, 2021
Modified: August 08, 2021
GABA
This page is from my personal notes, and has not been specifically reviewed for public consumption. It might be incomplete, wrong, outdated, or stupid. Caveat lector.- A major inhibitory neurotransmitter in the brain. Related to the action of ethanol and other depressants and anesthetics.
- TODO: understand better https://en.wikipedia.org/wiki/Gamma-Aminobutyric_acid
- Gamma-animobutyric acid
- 'butyric acid' is just butane with a carboxyl group
- it's 'gamma-amino' because there's an amino group attached to the gamma carbon. It is technically an amino acid, but not an 'alpha amino acid' like the ones that make proteins, which have the amino group attached to the 'alpha' carbon
- It is related to glutamate, an alpha-amino acid that has an extra carboxyl group attached to the same carbon as the amino group (in GABA this is the 'gamma' carbon, but in glutamate the attached carboxyl group makes it the 'alpha' carbon). It is synthesized from glutamate catalyzed by the enzyme glutamate decarboxylase (GAD).
- There are two kinds of GABA receptors:
- GABA_A receptors are ionotropic receptors. When activated, they open an ion channel allowing negatively-charged chloride ions (just chlorine with a full outer shell) into the cell. This makes the neuron less likely to fire.
- GABA_B receptors are G protein-coupled receptors (or 'metabotropic' receptors). These ultimately allow positively-charged potassium ions out of the cell, again making it less likely to fire.